Motor systems neuroscience is a branch of neuroscience rapidly gaining in importance. Whether one talks about clinical applications (such as using Deep Brain Stimulation as a treatment of Parkinson's disease or robotic rehabilitation devices for stroke patients) or basic science discoveries (recent findings of a surprising degree of plasticity in primary motor cortex), an understanding of how neural circuits control movement is critical to understanding how the brain works. At the same time, technological advances in bioengineering - such as the ability to record simultaneously from hundreds of neurons through multiple chronically implanted microelectrode arrays - have generated huge streams of data related to the neural control of movement. For these reasons, there has been a surge in theoretical (or computational) motor systems neuroscience research in an effort to codify our understanding of the global circuit principles that underlie motor learning and execution. Sophisticated mathematical theories and computational techniques are now routinely used to aid in the understanding of physiological data and behavioral findings. Given this rapid growth of theoretical motor systems neuroscience, there is concern of a growing divide between the computational scientists and the physiologists. In particular, continued progress depends on physiologists understanding the critical concepts the theorists are putting forward (regardless of whether they understand all the mathematical details) and on the theorists presenting their theories in ways that lead to testable consequences. The purpose of this satellite - an adjunct to the 2009 Neural Control of Movement conference -- is to foster better communication between theoreticians and experimentalists by grounding their interaction in the universal scientific language: experimental predictions. On four thematically-organized panels, key ideas in theoretical motor systems neuroscience (such as the synergy hypothesis and Bayesian optimality) will be discussed. The emphasis will be on determining the key empirical consequences of these ideas and discussing the likelihood of developing viable experimental strategies to test these predictions. The satellite is designed to cultivate group discussion with three discussants on every panel. PUBLIC HEALTH RELEVANCE: The field of motor systems neuroscience is concerned with understanding how the brain controls movement, so that we can better treat patients whose motor circuits have been compromised by disease or injury, such as stroke patients or patients with Parkinson's disease. Recently, there has been a surge of interest in theoretical (or computational) motor systems neuroscience to help organize large amounts of data with a few key mathematical principles. The purpose of this satellite is to foster better communication between the theoreticians and experimentalists working in the field by focusing on the key experimental predictions of a few important theoretical ideas.